A simple qualitative method for assessing microalbuminuria in diabetics

Diabetes mellitus is one of the most important causes of kidney diseases, the first sign of which is albuminuria. It is now possible to detect microalbuminuria before the appearance of larger quantities. We compared a simple qualitative test for microalbuminuria (change in color of a tablet containing bromphenol blue on addition of urine) with a more elaborate quantitative immunoturbidometric method. Of 109 samples tested 31 were positive by the quantitative method and 29 of these were positive by the tablet method. Out of the 78 negative by the quantitative method only 4 were positive by the qualitative test. The sensitivity of the tablet test was 93.5%, specificity 94.0%, positive predictive value 87.9%, negative predictive value 97.4%, false positive rate 5.2%, and false negative rate 6.2%. We conclude that the tablet test is simple and accurate and is suitable both for screening of large populations and for the diagnosis of individual cases of microalbuminuria.